1. Field of the Invention
The invention relates generally to systems and methods for cutting material, and can relate particularly to a shielded reciprocating surgical file system for cutting, removing, grinding, shaping and sculpturing bone and/or tissue material under direct vision.
2. Description of the Related Art
Adjacent spinal vertebrae are spaced by intervertebral discs that are tough and semi-elastic. The discs act as a flexible spacer between the vertebrae that makeup the backbone. Vertebrae are shaped to provide a bony tubular shaped tunnel between upper and lower pairs of vertebrae and this tunnel is made-up in part by the spacing disc. These tubular shaped tunnels are called neuroforamen and serve as a passageway for nerve roots. The size of the neuroforamen tubular shaped tunnels is a close fit for the nerve roots that pass through these tunnels on their way from the spinal cord to the arms, legs and other muscles.
Each year millions of people encounter neck and back injuries. Many million suffer from truly problematic back pain that either keeps them out of work or debilitates them in some way. Many vertebral and disc injuries result in pain from nerve irritation and compression.
When an intervertebral disc is damaged, often it is because of a physical overrotation between two vertebrae and normal wear and tear. When a vertebra is overrotated, small facet joints called the zygapophyseal capsules that are located to the left and right sides of the disc are damaged. When the body incurs damage to these small joints, unwanted osteophytes and bony overgrowths frequently occur at the edges of these tiny joints. The unwanted bony overgrowth restricts the neuroforamen and pinches the delicate and sensitive nerve roots.
Also, with age, for many people, the sensation of thirst is somewhat reduced. As a result, sometimes less water is consumed than needed by the body. The intervertebral discs depend on water as well as other materials to maintain a healthy function. When a disc loses a part of its fluid mass it is said to desiccate. When a disc is desiccated it reduces in height and reduces the space between the two vertebras it is connected to, that is, the neuroforamen becomes constricted and pinches nerve roots.
Pinched nerves that are constrained in between vertebras can cause neck and back pain. The bony overgrowth and a reduction in the space between vertebras pinch the nerves causing irritation, pain and numbness. The pinching can potentially result in a loss of use of the limbs controlled by the affected nerve.
Thus, when intervertebral discs are damaged from accident, age and/or general wear and tear the intervertebral nerve roots in the neuroforamen are irritated and pinched and can cause unwanted involuntary muscular contractions. The muscle contractions can come in the form of a continuous low-grade ache or become more severe as a spasm. The muscle contractions can act to further compress the space between the vertebras, which further pinches the nerve. This becomes a severely painful, self-destructive and self-feeding problem.
One current technology to treat a patient with nerve compression that causes pain and numbness involves the removal of the disc and fusion of the vertebra below with the vertebra above it. Vertebral fusion removes a disc that was flexible and fuses one vertebra together with the adjacent vertebra resulting in a rigid joint between two vertebrae. This causes added strain on the disc above and below the now rigid bone fusion. Sometimes the attempted fusion of one vertebra onto another vertebra is unsuccessful and does not provide the intended fusion.
Disadvantageously, the intervertebral fusion is an invasive and relatively complicated procedure. In addition, and undesirably, the fusion process can result in a long hospital stay for the patient, a long recuperation and rehabilitation period and high costs for both the patient and care providers.